The present invention relates to a method for observing and inspecting a defect that has occurred during the manufacture of a semiconductor product, and a defect inspection device using the same.
In order to secure earnings in the manufacture of a semiconductor wafer, it is important to quickly start up a manufacturing process thereof to thereby cause transition to a high-yield mass production system to take place at an early stage. For this purpose, various types of inspection • measurement devices are introduced into a production line. For the purpose of deciding a process condition enabling a desired circuit pattern to be formed at an early stage, a procedure has been in practice whereby a plurality of wafers or chips are prepared by intentionally varying, for example, a process condition in a process startup stage, an inspection is performed against the wafers or the chips, and a process condition is decided on the basis of a result of the inspection. Meanwhile, an inspection on a wafer in a mass production stage is performed for the purpose of process monitoring. More specifically, a sampling inspection of a wafer is performed in a stage halfway through the manufacture of the wafer to thereby examine whether or not a defect has occurred to the surface of the wafer, or whether or not abnormality is present on a circuit pattern formed on the surface of the wafer. If a defect or abnormality of the circuit pattern is detected as a result of the inspection, the cause thereof is looked into, and a necessary countermeasure is taken.
A defect observation device is a device for capturing a high-resolution image of detect coordinates of a wafer, using the output of the other inspection device, thereby outputting the image. Since progress has since been made in the miniaturization of a semiconductor manufacturing process to be accompanied by a defect size reaching to the order of several tens of nm, resolution on the order of several nm is required in order to observe a defect in detail. For this reason, an observation device (hereinafter referred to as a Review SEM) using a scanning electron microscope (SEM) has lately been in widespread use. A method for detecting a defect by comparing a captured-image of a defective site with an image of a non-defective product is described in Japanese Unexamined Patent Application Publication No. 2001-189358. Further, a method for detecting a defect from one sheet of an image that has captured a defective site, is described in Japanese Unexamined Patent Application Publication No. 2007-40910.
A method for deciding coordinates on a wafer, the coordinates being those to be reviewed between defect reviews, in an inspection device having not less than two inspection systems, is described in U.S. Pat. No. 7,904,845.